Implemented the Sum Function

MathPad/MPSumFunctionLayout.m

@@ -0,0 +1,35 @@
+//
+//  MPSumFunctionLayout.m
+//  MathPad
+//
+//  Created by Kim Wittenburg on 23.04.14.
+//  Copyright (c) 2014 Kim Wittenburg. All rights reserved.
+//
+
+#import "MPSumFunctionLayout.h"
+#import "MPSumFunction.h"
+
+@implementation MPSumFunctionLayout
+
+- (MPSumFunction *)sumFunction
+{
+    return (MPSumFunction *)self.function;
+}
+
+- (NSSize)calculateSize
+{
+    NSAttributedString *text = [[NSAttributedString alloc] initWithString:@"∑" attributes:@{NSFontAttributeName: [NSFont fontWithName:@"HelveticaNeue" size:50.0]}];
+    [self.textStorage setAttributedString:text];
+    NSRange glyphRange = [self.layoutManager glyphRangeForTextContainer:self.textContainer];
+    return [self.layoutManager boundingRectForGlyphRange:glyphRange inTextContainer:self.textContainer].size;
+}
+
+- (void)drawFunctionAtPoint:(NSPoint)point
+{
+    NSAttributedString *text = [[NSAttributedString alloc] initWithString:@"∑" attributes:@{NSFontAttributeName: [NSFont fontWithName:@"HelveticaNeue" size:50.0]}];
+    [self.textStorage setAttributedString:text];
+    NSRange glyphRange = [self.layoutManager glyphRangeForTextContainer:self.textContainer];
+    [self.layoutManager drawGlyphsForGlyphRange:glyphRange atPoint:point];
+}
+
+@end